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Antony Hewish - Biographical

I was born in Fowey, Cornwall, on 11 May
1924, the youngest of three sons and my father was a banker. I
grew up in Newquay, on the Atlantic coast and there developed a
love of the sea and boats. I was educated at King's College,
Taunton and went to the University of Cambridge in 1942. From 1943-46 I was
engaged in war service at the Royal Aircraft Establishment,
Farnborough and also at the Telecommunications Research
Establishment, Malvern. I was involved with airborne
radar-counter-measure devices and during this period I also
worked with Martin Ryle.

Returning to Cambridge in 1946 I graduated in 1948 and
immediately joined Ryle's research team at the Cavendish
Laboratory. I obtained my Ph.D. in 1952, became a Research Fellow
at Gonville and Caius College where I had been an undergraduate,
and in 1961 transferred to Churchill College as Director of Studies in
Physics. I was University Lecturer during 1961-69, Reader during
1969-71 and Professor of Radio Astronomy from 1971 until my
retirement in 1989. Following Ryle's illness in 1977 I assumed
leadership of the Cambridge radio astronomy group and was head of
the Mullard Radio Astronomy Observatory from 1982-88.

My decision to begin research in radio astronomy was influenced
both by my wartime experience with electronics and antennas and
by one of my teachers, Jack Ratcliffe, who had given an excellent
course on electromagnetic theory during my final undergraduate
year and whom I had also encountered at Malvern. He was head of
radiophysics at the Cavendish Laboratory at that time.

My first research was concerned with propagation of radiation
through inhomogeneous transparent media and this has remained a
lifelong interest. The first two radio "stars" had just been
discovered and I realised that their scintillation, or
"twinkling", could be used to probe conditions in the ionosphere.
I developed the theory of diffraction by phase-modulating screens
and set up radio interferometers to exploit my ideas. Thus I was
able to make pioneering measurements of the height and physical
scale of plasma clouds in the ionosphere and also to estimate
wind speeds in this region. Following our Cambridge discovery of
interplanetary scintillation in 1964 I developed similar methods
to make the first ground-based measurements of the solar wind and
these were later adopted in the USA, Japan and India for long
term observations. I also showed how interplanetary scintillation
could be used to obtain very high angular resolution in radio
astronomy, equivalent to an interferometer with a baseline of
1000 km - something which had not then been achieved in this
field. It was to exploit this technique on a large sample of
radio galaxies that I conceived the idea of a giant phased-array
antenna for a major sky survey. This required instrumental
capabilities quite different from those of any existing radio
telescope, namely very high sensitivity at long wavelengths, and
a multi-beam capability for repeated whole-sky surveys on a day
to day basis.

I obtained funds to construct the antenna in 1965 and it was
completed in 1967. The sky survey to detect all scintillating
sources down to the sensitivity threshold began in July. By a
stroke of good fortune the observational requirements were
precisely those needed to detect pulsars. Jocelyn Bell joined the
project as a graduate student in 1965, helping as a member of the
construction team and then analysing the paper charts of the sky
survey. She was quick to spot the week to week variability of one
scintillating source which I thought might be a radio flare star,
but our more detailed observations subsequently revealed the
pulsed nature of the signal.

Surprisingly, the phased array is still a useful research
instrument. It has been doubled in area and considerably improved
over the years and one of my present interests is the way our
daily observations of scintillation over the whole sky can be
used to map large-scale disturbances in the solar wind. At
present this is the only means of seeing the shape of
interplanetary weather patterns so our observations make an
useful addition to in-situ measurements from spacecraft
such as Ulysses, now (1992) on its way to Jupiter.

Looking back over my forty years in radio astronomy I feel
extremely privileged to have been in at the beginning as a member
of Martin Ryle's group at the Cavendish. We were a closely-knit
team and besides my own research programmes I was also involved
in the design and construction of Ryle's first antennas employing
the novel principle of aperture synthesis.

Teaching physics at the University, and more general lecturing to
wider audiences has been a major concern. I developed an
association with the Royal Institution in London when it was
directed by Sir Lawrence Bragg, giving one of the well known
Christmas Lectures and subsequently several Friday Evening
Discourses. I believe scientists have a duty to share the
excitement and pleasure of their work with the general public,
and I enjoy the challenge of presenting difficult ideas in an
understandable way.

I have been happily married since 1950. My son is a physicist and
obtained his Ph.D. for neutron scattering in liquids, while my
daughter is a language teacher.

This autobiography/biography was written
at the time of the award and later published in the book series Les
Prix Nobel/Nobel Lectures/The Nobel Prizes. The information is sometimes updated with an addendum submitted
by the Laureate.